Because of requirements on Oil and Gas (O & G) operators, typically from environmental authorities to monitor environmental impacts during Oil and Gas (O & G) drilling activities in sensitive environments such as a deep-water sea-floor with corals, there is a need to monitor coral status and impact on this environment, especially during such activities. Guidelines have been prepared to mitigate the environmental risk of drilling activities in areas with coral populations (Den Norske Veritas, DNV, 2012). In areas where drilling activities are close to coral populations, such as areas with coral reefs, the O&G operators typically have to apply costly mitigation actions to protect the corals. This often leads to applying a precautionary principle as there is no current technology known to document impact and monitor coral, or other deep-sea species, status during drilling activities.
Until now, according to our best understanding, there are no known techniques to measure effect on coral status or other deep-sea species continuously. Current techniques to assess impact of drill cutting plumes used by O&G operators are based on current measurements, turbidity measurements, sediment traps, sediment samples and visual mapping, all techniques typically not being continuously.
References describing known techniques and background are listed under the heading “list of references” in this disclosure.
Regarding monitoring such as visual mapping, for instance, the Guidelines (DNV, 2012) states that in general it is difficult to find an appropriate parameter for monitoring directly of corals, which will reflect any influences from drilling activities. High resolution still photos have from experience not been able to identify change in polyp behaviour on corals such as Lophelia pertusa when exposed to drill cutting sedimentations such as drill cutting plumes.
In particular, none of the known techniques are providing an actual measurement of the impact or changes of coral end-points from drill cutting sedimentations, but are only proxy measurements of drill cutting potential exposure, not their effect.